Integrated circuits (“ICs”) are incorporated into many electronic devices. IC packaging has evolved, such that multiple ICs may be vertically stacked in so-called three-dimensional (“3D”) packages in order to save horizontal area on a printed circuit board (“PCB”). An alternative packaging technique, referred to as a 2.5D package may use an interposer, which may be formed from a semiconductor material such as silicon, for coupling one or more dies to a PCB. An interposer is an intermediate layer often used for interconnection routing or as a ground/power plane for different IC chips. A plurality of IC chips, which may be of homogenous or heterogeneous technologies, are mounted on the interposer. Connections among the various ICs are routed through conductive patterns in the interposer. ESD protection in current 2.5D/3D IC applications is limited to intra-chip ESD protection without any chip-to-chip ESD discharge path.